Connector assembly



P 1965 M. N. BROWN ETAL 3,206,717

CONNECTOR AS SEMBLY Filed June 12, 1962 INVENTOR. 9'4- Nmcom N. BROwN I I BY FRaNK B. STeRK MAWw-W United States Patent 3,206,717 CUNNECTUR ASSEMBLY Malcolm N. Brown, Camp Hill, and Frank B. Stark,

Harrisburg, Pa, assignors to AMP Incorporated, Harrisburg, Pa.

Filed June 12, 1962, Ser. No. 201,374 3 Claims. (Cl. 3392il5) This invention relates to an improved connector assembly of the type utilized to mechanically and electri cally interconnect signal conductors in a secure and reliable manner.

The electrical characteristics of many electronic components are such that impedance variations in signal paths interconnecting such components can not be tolerated. For this reason, soldered interconnections are frequently utilized even though soldering techniques involve considerable installation time and cost and do not provide a connect-disconnect function. As an approach to signal path impedance problems overcoming the principal shortcomings of soldering techniques a number of plug and socket electrical connectors have been developed incorporating resilient spring members adapted to be loaded by conductive pin members attached to the conductor being connected. One of the problems with connectors of this type lies in the requirement calling for a considerable spring force acting upon a sufiicient area of a conductor pin to form a stable interface contact which will not produce impedance variations when the assembly is subjected to vibration or sudden displacement. One prior art approach to this problem features a contact spring formed by bifurcated arms adapted to be forced apart by a conductor pin inserted therebetween. In order to get a sufiicient resiliency and contact area the bifurcated members must be relatively long. Another prior art approach utilizes a series of U-shaped contact fingers integrally formed on a flat base portion. Assemblies of this type are also relatively long and the contact fingers thereof, while providing a sufficient bearing force against a contact pin inserted therein, have little or no resiliency, thus making pin insertion and withdrawal diificult. Furthermore, contact assemblies of this type have relatively small contact areas and may be vibration sensitive.

A further problem confronting spring type connector assemblies lies in the fact that the contact area is frequently provided with a coating of low resistance, corrosion resistant material such as a nickel-gold plating. As will be appreciated, such coating will be less likely to withstand long usage if the member upon which it is coated is a resilient member subjected to flexure and surface bending.

A still further problem confronting the use of resilient spring members lies in the fact that in many devices the spring member has no positive means of alignment and may become displaced so as to make insertion of a complementary pin member in the proper position diflicult, if not impossible.

Accordingly, it is one object of the present invention to provide an improved contact assembly having a novel resilient spring capable of achieving high contact forces in a relatively short length.

It is another object of invention to provide a connector assembly having an improved resilient spring member held in positive alignment against undesirable displacement.

It is a further object of invention to provide an improved spring loaded connecting device adapted to achieve a mechanical and electrical interconnection with a connector pin member in a stable and reliable manner.

The foregoing objects are attained by the present invention through the use of a novel contact member having a sleeve extension relieved to accommodate a double cantilever spring member cooperatively secured to end portions of the sleeve extension. The relationship of the cantilever spring member and the contact member sleeve extension are such that the insertion of a connector pin within the extension will tend to flatten the spring which in turn operates to press the connector pin against the interior of the sleeve under considerable force. The cantilevered spring member includes a provision at each end engaging the surfaces of the contact member sleeve extension and adapted to maintain a positive alignment of the spring member relative to the sleeve extension.

In the drawings:

FIGURE 1 is a perspective of a contact assembly block including a sectional view of the connector assembly of the invention in one embodiment;

FIGURE 2 is a longitudinal section of the connector assembly of the invention in another embodiment showing the assembly components in detail;

FIGURE 3 is a perspective view of the components of the assembly shown in FIGURE 2;

FIGURE 4 is a schematic diagram showing the operation of the assembly of the invention in progressive stages;

FIGURE 5 is a longitudinal section of a further embodiment of the assembly of the invention including dual conact and spring members; and

FIGURE 6 is a longitudinal section of yet a further embodiment having dual contact and spring components.

Referring now to FIGURE 1, there is shown an insulating block 10 housing a plurality of contact assemblies 12 of the type contemplated by the invention. As indicated in FIGURE 1, each of the assemblies 12 is adapted to accommodate the insertion of conductor pin members at each end to thereby form an electrical interconnection between two conductors. More particularly, a conductor pin, such as 26, may be inserted within an assembly 12 through an assembly aperture 22 and driven into the position shown with respect to conductor pin 24 to provide an interconnection with contact component 14 through its sleeve extension 16. At the opposite end of component 14 is an additional contact portion shown in this embodiment as a tapered sleeve 28 adapted to receive a conductor taper pin, such as 30. from the description herein to follow that while the as semblies shown in FIGURE 1 are indicated as accommodating individual conductors on each end thereof, such assemblies may be utilized with commonly mounted or ganged conductor plugs adapted to engage a plurality of such assemblies. It is further contemplated that as an alternative embodiment the contact portion at the portion indicated as 18 may interconnect printed circuit paths or may be adapted to form connector portions to receive and terminate fine wire conductors in the manner shown and described in US patent application S.N. 20,049 to James C. Heselwood.

While the assemblies of the invention are shown as mounted in an insulating block member in FIGURE 1, one of the principle advantages of the assembly of the invention may best be appreciated from FIGURES 2 and 3 depicting the assembly of the invention in one embodiment prior to mounting. As will be apparent, the assembly is comprised of but two components; a contact member 32 and a spring member 44. Contact member 32 includes a central portion 33, a sleeve portion 40 and a sleeve extension portion 34. The surface areas of the flange extending from portion 33 and the outside surface of sleeve 40 serves to define bearing areas permitting the assembly to be mounted in an insulating block substantially smaller than that indicated in FIGURE 1 and serve to make the assembly ideally suited for use with typical printed circuit board thicknesses.

It will be apparent The extension 34, integral with portion 33 and sleeve 40, serves to position, align and secure spring 44 and and, in so doing, eliminates any need for a separate spring mounting member. When the assembly is utilized in an insulating block as shown in FIGURE 1, this feature operates to eliminate the need for block apertures carried to a close tolerance; the spring being positively aligned by extension 34.

As will be apparent from FIGURES 2 and 3, extension 34 includes a slot or breach 37 extending for a substantial portion of its length between circular sleeve segments 36 and 39 aligned to form a bore 38 extending the length of the sleeve extension. The outside surfaces of segments 36 and 39 serve to support spring member 44 and the inside bore 38 serves to position and receive the insertion of a contact pin member.

Spring 44 includes barrel portions 48 and 52 having a common extension 46 forming a resilient double cantilever spring. Barrel portion 48 is adapted to fit over and be supported by sleeve segment 36 of extension 34; barrel portion 52 being similarly supported and positioned over segment 39 of extension 34. In its normal unstressed position, spring 46 nests within slot 37, as indicated in FIGURE 2, and the flange portion 50 of barrel 48 rests against the end of segment 36. The interior length of portion 48 relative to the displacement possible when spring 46 is flattened must be sufficient to maintain circular contact with segment 36 so as to prevent the spring end from being forced off extension 34. In operation, a connector pin member inserted in bore 38 will be guided along slot 37 deflecting spring 46 and driving the spring barrel portion 48 outwardly; the barrel portion 52 being held against axial movement by its abutment with portion 33.

Upon withdrawal of the connector pin member, spring 44 is held against being axially displaced from extension 34 by means of flange at the end of barrel 52 and interlocked with a groove or notch 43 disposed in sleeve extension segment 39. Flange 53 and groove 43 further cooperate to prevent rotational misalignment of spring 44 relative to the sleeve extension. As a result of the above described spring action, a connector pin inserted within bore 38 will be forced into contact with the bottom surface 41 of sleeve 34 to electrically and mechanically interconnect the pin with component 32.

This is shown more clearly in FIGURE 4 wherein the insertion of pin P is first shown striking spring 46 and producing the forces F and F the former acting to resist insertion of the pin and the latter resulting in the pin being forced against the lower portion of extension 34, shown as 41, and thereby into a scrubbing contact With contact component 32. Further insertion of P will deflect spring 46, the resulting flattening of the spring driving barrel 48 outwardly and generating a force F which is the sum of the forces attributable to each spring extension from barrels 48 and 52, effectively acting as a double cantilever. Once spring 46 has been lifted by the end of the pin member, the ramainder of pin travel will take place with the lower surface of the pin member being forced against the sleeve extension contact surface 41 by F It has been found that the particular force vectors extant during pin travel result in a substantial wiping of the area of contact with a resulting electrical connection between pin and sleeve which is both stable and of low electrical resistance. Because the principal area of contact is with the extension surface 41, only such surface need be plated with corrosion resistant metals. Additionally, the V-shaped spring 44 through being held at its end against relative transverse movement by barrel portions 48 and 52 results in a considerably higher force per unit length than is possible with a spring not so restricted.

FIGURE shows an embodiment of the contact assembly of the invention capable of accommodating the insertion of two connector pin members. In this embodiment, the connector component 71 includes a centrally disposed flange 72, having opposed sleeve extension segments '74 and 76 adapted to receive and position spring members 78 and 80. The component 71 and, in turn, the sleeve extension segments and spring members are supported Within an insulating block 70 engaging the flange 72 and apertured to receive the spring sleeve assemblies. With this embodiment, a connector pin may-be inserted from each side of the assembly as at 82 and 84 and driven into the particular contact described with respect to FIG- URES 2, 3 and 4. As in the above embodiment, the springs 78 and are held against outward movement by flanges 79 and 81, cooperatively engaging sleeve segment slots 75 and 77.

Referring now to FIGURE 6, a further embodiment is shown mounted in an insulating board by means of an eyelet 92 flared at each end to interlock the contact assembly by a gripping relation with the assembly flange 96. The component 94 includes a sleeve 99 having three circular segments 100, 102 and 104, separated by longitudinal slots 106 and 108, defining a longitudinal passage 93 extending through the sleeve extension. Component 94 further includes an interior sleeve 98 in an interconnecting alignment with the passage of the sleeve segments. Secured to the sleeve extension is a spring member 110 having barrel portions 112, 114 and 116 supported by the sleeve extension segments 104, 102 and 100, and interconnected by integral spring members 118 and 120 fitted within the longitudinal slots of the sleeve extension. The assembly of FIGURE 6 is adapted to receive insertion of a contact pin from either end as at apertures 93 and 98. Sleeve 99 includes a relative slot 101 adapted to receive a spring flange 111 to resist axial displacement of the spring member.

In an actual unit constructed in accordance with FIG- URE 2 the contact component was formed of beryllium copper and included a plating in the sleeve extension of gold over nickel. The spring member for such assembly was manufactured of stainless steel. The sleeve extension of the unit was approximately 0.356 inch in length having an external diameter of 0.033 inch and an internal diameter of 0.019 inch and including a slot approximately 0.130 inch long. The spring of the unit included barrel portions having inner diameters of approximately 0.034 inch and lengths of approximately 0.030 inch separated by a spring portion approximately 0.130 inch long having joined cantilevered arms inclined at approximately 30 degrees in their normal unflattened position.

Changes in construction will occur to those skilled in the art and various apparently different modifications and embodiments may be made without departing from the scope of the invention. The matter set forth in the foregoing description and accompanying drawings is offered by way of illustration only. The actual scope of the invention is intended to be defined in the following claims when viewed in their proper perspective against the prior art.

We claim:

1. A device for interconnecting electrical conductors comprising in combination a contact assembly having a contact portion including a central passage adapted to receive a connector pin member, the contact portion further including sleeve segments at each end separated by a slot extending therebetween forming an entry into said central passage, a resilient spring member mounted on said contact portion, said spring member including a first barrel portion affixed to one sleeve segment against axial movement relative to said contact portion and a second barrel portion having an interior surface substantially surrounding the other sleeve segment and free for axial movement outwardly of said contact portion, the second barrel tion including at the outer end thereof an inwardly directed! radial flange adapted to engage the outer end efsaid. other;

sleeve segment to limit said second barrel portion against movement axially inward of said contact portion, said spring member further including a spring arm of flat stock formed inwardly into the entry of said central passage and supported by said first and second barrel portions whereby insertion of the connector pin member into said contact portion passage pushes the arm radially outwardly with said second barrel portion driven axially to drive said pin against the contact portion central passage surface and a support means having an aperture receiving said contact assembly, said aperture being so sized as to surround the said spring member barrel portions and slidingingly receive the said second barrel portion to permit movement of said second barrel portion and to support said spring member and contact portion against relative transverse movement in said support means.

2. The device of claim 1 wherein the spring arm of said spring member is formed to include a V-shaped section supported by relatively straight portions extending from the barrel portions.

3. The connector of claim 1 wherein the spring member includes a third barrel portion disposed between said first and second barrel portions and the spring arm of said spring member includes a V-shaped section supported by integral relatively straight portions extending axially from each end of the third barrel portion.

References Cited by the Examiner UNITED STATES PATENTS 2,206,672 7/40 Pederquist 3 3 9262 X 2,958,845 11/60 Dupre et al. 339--273 3,086,190 4/63 Neidecker et al. 1- 339252 3,141,723 7/64 Bonhomme 339-256 FOREIGN PATENTS 618,055 12/26 France. 1,25 5,03 7 l/ 61 France. 1,123,728 2/62 Germany.

643,627 9/50 Great Britain.

JOSEPH D. SEERS, Primary Examiner. 

1. A DEVICE FOR INTERCONNECTING ELECTRICAL CONDUCTORS COMPRISING IN COMBINATION A CONTACT ASSEMBLY HAVING A CONTACT PORTION INCLUDING A CENTRAL PASSAGE ADAPTED TO RECEIVE A CONNECTOR PIN MEMBER, THE CONTACT PORTION FURTHER INCLUDING SLEEVE SEGMENTS AT EACH END SEPARATED BY A SLOT EXTENDING THEREBETWEEN FORMING AN ENTRY INTO SAID CENTRAL PASSAGE, A RESILIENT SPRING MEMBER MOUNTED ON SAID CONTACT PORTION, SAID SPRING MEMBER INCLUDING A FIRST BARREL PORTION AFFIXED TO ONE SLEEVE SEGMENT AAINST AXIAL MOVEMENT RELATIVE TO SAID CONTACT PORTION AND A SECOND BARREL PORTION HAVING AN INTERIOR SURFACE SUBSTANTIALLY SURROUNDING THE OTHER SLEEVE SEGMENT AND FREE FOR AXIAL MOVEMENT OUTWARDLY OF SAID CONTACT PORTION, THE SECOND BARREL PORTION INCLUDING AT THE OUTER END THEREOF AN INWARDLY DIRECTED RADIAL FLANGE ADAPTED TO ENGAGE THE OUTER END OF SAID OTHER SLEEVE SEGMENT TO LIMIT SAID SECOND BARREL PORTION AGAINST MOVEMENT AXIALLY INWARD OF SAID CONTACT PORTION, SAID SPRING MEMBER FURTHER INCLUDING A SPRING ARM OF FLAT STOCK FORMED INWARDLY INTO THE ENTRY OF SAID CENTRAL PASSAGE AND SUPORTED BY SAID FIRST AND SECOND BARREL PORTIONS WHEREBY INSERTION OF THE CONNECTOR PIN MEMBER INTO SAID CONTACT PORTION PASSAGE PUSHES THE ARM RADIALLY OUTWARDLY WITH SAID SECOND BARREL PORTION DRIVEN AXIALLY TO DRIVE SAID PIN AGAINST THE CONTACT PORTIONS CENTRAL PASSAGE SURFACE AND A SUPPORT MEANS HAVING AN APERTURE RECEIVING SAID CONTACT ASSEMBLY, SAID APERTURE BEING SO SIZED AS TO SUR ROUND THE SAID SPRING MEMBER BARREL PORTIONS AND SLIDINGINGLY RECEIVE THE SAID SECOND BARREL PORTION TO PERMIT MOVEMENT OF SAID SECOND BARREL PORTION AND TO SUPPORT SAID SPRING MEMBER AND CONTACT PORTION AGAINST RELATIVE TRANSVERSE MOVEMENT IN SAID SUPPORT MEANS. 